• Title/Summary/Keyword: Flight vehicles

Search Result 300, Processing Time 0.024 seconds

Path Generation Method of UAV Autopilots Using Max-Min Algorithm

  • Kwak, Jeonghoon;Sung, Yunsick
    • Journal of Information Processing Systems
    • /
    • v.14 no.6
    • /
    • pp.1457-1463
    • /
    • 2018
  • In recent times, Natural User Interface/Natural User Experience (NUI/NUX) technology has found widespread application across a diverse range of fields and is also utilized for controlling unmanned aerial vehicles (UAVs). Even if the user controls the UAV by utilizing the NUI/NUX technology, it is difficult for the user to easily control the UAV. The user needs an autopilot to easily control the UAV. The user needs a flight path to use the autopilot. The user sets the flight path based on the waypoints. UAVs normally fly straight from one waypoint to another. However, if flight between two waypoints is in a straight line, UAVs may collide with obstacles. In order to solve collision problems, flight records can be utilized to adjust the generated path taking the locations of the obstacles into consideration. This paper proposes a natural path generation method between waypoints based on flight records collected through UAVs flown by users. Bayesian probability is utilized to select paths most similar to the flight records to connect two waypoints. These paths are generated by selection of the center path corresponding to the highest Bayesian probability. While the K-means algorithm-based straight-line method generated paths that led to UAV collisions, the proposed method generates paths that allow UAVs to avoid obstacles.

A Study on the Flight Vibration Environmental Specification of Unmanned Flying Vehicle using Random Vibration Test and Analysis Methods (랜덤 진동 시험 및 해석 기법을 이용한 무인 비행체의 비행 진동 환경 규격 연구)

  • Jangseob, Choi;Dongho, Oh
    • Journal of the Korea Institute of Military Science and Technology
    • /
    • v.25 no.6
    • /
    • pp.596-605
    • /
    • 2022
  • In this study, analysis of dynamic characteristics and flight vibration was performed to unmanned aerial vehicles. The analysis model was supplemented by performing a dynamic characteristic test and a random vibration test using manufactured dummy aerial vehicle. For the dynamic characteristic test, a bungee cable was used to implement the free end boundary condition. Prior to the flight vibration test using a multiple electric shaker, a random vibration test was performed to predict the excitation force during the actual flight vibration test. It was judged that the actual test could be predicted more accurately by supplementing the analysis model from the test results. In addition, it was possible to determine the feasibility of the test by predicting the excitation force of the flight vibration test.

Fusion Filter for the Trajectory and Instantaneous Impact Point Estimation of a Satellite Launch Vehicle (위성발사체 궤도 및 순간낙하점 추정을 위한 융합필터)

  • Ryu, Seong-Sook;Kim, Jeong-Rae;Song, Yong-Kyu;Ko, Jeong-Hwan;Sim, Hyung-Seok
    • Journal of Advanced Navigation Technology
    • /
    • v.12 no.4
    • /
    • pp.295-303
    • /
    • 2008
  • Malfunction of satellite launch vehicles with high speed and long range can be a major concern for operations. Flight safety system that monitor the trajectory and identify any failure of the launch vehicles. Tracking filters for the flight safety systems are different from common tracking filters since filter reliability is more emphasized than accuracy. Reliable estimation of instantaneous impact points requires reliable velocity estimates as well as reliable position estimates. A fusion filter for a flight safety system was developed with the tracking sensor models for the Korea Satellite Launch Vehicle I. The fusion filter performances were evaluated by analyzing the trajectory and instantaneous impact point estimates.

  • PDF

A Study on the design of Unmanned Autonomous Helicopter for Aerial Monitoring and Control of a Large Size Disaster and Forest Fire (대형재난 및 산불 공중지휘통제용 무인자율헬기 개발에 관한연구)

  • Kim, Jong-Kwon;Kwark, Ji-Hyun;Son, Bong-Sei
    • Proceedings of the Korea Institute of Fire Science and Engineering Conference
    • /
    • 2008.11a
    • /
    • pp.105-110
    • /
    • 2008
  • Unmanned helicopter has several abilities such as vertical take off, hovering, low speed flight at a specific altitude. Such vehicles are becoming popular in actual applications such as search and rescue, aerial reconnaissance and surveillance in the case of a large size disaster and forest fire. In this paper, a flight control system was designed for an unmanned helicopter. This paper was concentrated on describing the systematic design, electronic equipments and their interconnections for realizing the autonomous flight and aerial monitoring. A study on the autonomous waypoint navigation and altitude control performance were performed and tested on a test unmanned helicopter and the performance and the feasibility were represented.

  • PDF

Design and Implementation of UAV's Autopilot Controller

  • Lee, Jeong-Hwan;Lee, Ki-Sung;Jeong, Tae-Won
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 2004.08a
    • /
    • pp.52-56
    • /
    • 2004
  • Unmanned Aerial Vehicles (UAVs) are remotely piloted or self-piloted aircraft by inputted program in advance or artificial intelligence. In this study Aileron and Elevator are used to control the movement of airplane for horizontal and vertical flights about its longitudinal and lateral axis. In an introduction, the drone was linearly modeled by extracting aerodynamic parameter through flight test and simulation, lift and drag coefficient corresponding to angle of attack, changes of pitching moment coefficient. In the main subject, the flight simulation was performed after constructing hardware using TMS320F2812 from TI company and PID with lateral and longitudinal controller for horizontal and vertical flights. Flying characteristics of two system were estimated and compared through real flight test with hardware equipped algorithm and adaptive algorithm that was applied to consider external factors such as turbulence. In conclusion the control performance of the controller with proposed algorithm was streamlined at lateral and longitudinal controller respectively, we will discuss guidance command to pass way point.

  • PDF

A Real-Time NDGPS/INS Navigation System Based on Artificial Vision for Helicopter (인공시계기반 헬기용 3차원 항법시스템 구성)

  • Kim, Jae-Hyung;Lyou, Joon;Kwak, Hwy-Kuen
    • Journal of the Korea Institute of Military Science and Technology
    • /
    • v.11 no.3
    • /
    • pp.30-39
    • /
    • 2008
  • An artificial vision aided NDGPS/INS system has been developed and tested in the dynamic environment of ground and flight vehicles to evaluate the overall system performance. The results show the significant advantages in position accuracy and situation awareness. Accuracy meets the CAT-I precision approach and landing using NDGPS/INS integration. Also we confirm the proposed system is effective enough to improve flight safety by using artificial vision. The system design, software algorithm, and flight test results are presented in details.

Analysis of Flight Performance Reserve for Upper Stage of Satellite Launch Vehicles (위성발사체 상단의 비행성능여유 분석)

  • Song, Eun-Jung;Choi, Jiyoung;Cho, Sang-bum;Sun, Byung-Chan
    • Journal of the Korean Society for Aeronautical & Space Sciences
    • /
    • v.45 no.5
    • /
    • pp.386-392
    • /
    • 2017
  • This paper considers the analysis of the flight performance reserve, which is required propellant to compensate various launch vehicle performance deviations, to inject the payload of a 3-staged launch vehicle to a circular sun synchronous orbit at a height of 700 km. The various error sources, which affect the orbit injection accuracy, and their uncertainty are defined first. Then the sensitivity analysis, which has the advantage that each error source effect can be investigated independently, is performed for the extreme ${\pm}3{\sigma}$ conditions of the launch vehicle performance errors. Monte carlo simulations are also conducted to compute the propellant reserve, which can consider the combined effects of each error source. Finally the obtained flight performance reserves by the two approaches are compared and it is confirmed that they show similar results.

Autopilot design for BTT flight vehicles (이동중인 비행시스템의 자동조종장치 설계)

  • 백운보;허남수;이만형;황창선
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 1989.10a
    • /
    • pp.87-92
    • /
    • 1989
  • An autopilot for the class of Bank-To-Turn missiles is developed using a multivariable plant model & control design methodology. The roll-pitch-yaw cross coupling is included in the design considerations. Feedback system is designed using the Linear Quadratic Gaussian with Loop Transfer Recovery (LQG/LTR). Nonlinear simulations are presented to demonstrate the performances of the designed system.

  • PDF

Roll motion control of flight vehicles using rollerons (롤러론에 의한 비행체 롤 운동 제어)

  • 김병교;김요섭
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 1986.10a
    • /
    • pp.251-255
    • /
    • 1986
  • Some missiles using canards as control device adopt rollerons to reduce roll motion due to aerodynamically induced rolling moment. This paper presents equations of motion of these missiles including the gyroscopic effect of rolleron rotors. Some linearized analysis results and simulation results are shown to coincide, thus some characteristic motions of missiles and rollerons can be seen.

  • PDF

Performance Analyses of the GPS Receiver for Satellite Launch Vehicles according to Temperature Variation (온도변화에 따른 위성발사체용 GPS 수신기의 성능분석)

  • Kwon, Byung-Moon;Moon, Ji-Hyeon;Choi, Hyung-Don;Cho, Gwang-Rae
    • Journal of the Korean Society for Aeronautical & Space Sciences
    • /
    • v.33 no.12
    • /
    • pp.101-108
    • /
    • 2005
  • The GPS(Global Positioning System) receiver for satellite launch vehicles which will be mounted on a launch vehicle can be applied to the flight safety system with its accurately calculated position and velocity data during vehicle's flight. This paper analyzes the performance of the GPS receiver such as SNR(Signal to Noise Ratio), fix mode, position and velocity error, number of visible and tracking satellites, and PDOP(Position Dilution of Precision) under temperature variation which is changed from -34$^{\circ}C$ to +71$^{\circ}C$.